Vesicoureteral Reflux

Vesicoureteral reflux (VUR) is a common urinary condition, which is especially detected in infants and young children who regularly suffer from urinary tract infections (UTI). Find out more about the ailment including its types, symptoms, causes, diagnosis, and treatment methods.

Vesicoureteral reflux Definition

It is a functional disorder of the urinary system characterized by a retrograde flow of urine from the bladder into the ureters or kidneys. This can lead to serious health consequences. The urinary tract is the drainage system of the body that mainly attributes to removal of wastes and excessive fluids. The kidneys are normally responsible for filtration of blood and to produce urine that travels via the ureters to the bladder for final elimination. In VUR, however, the flow of urine follows a reversal pattern that puts a large number of patients at an increased risk of kidney damage.

Vesicoureteral reflux Types

On the basis of the underlying cause, VUR can be classified into two forms:

Picture 1 – Vesicoureteral reflux

  • Primary vesicoureteral reflux
  • Secondary vesicoureteral reflux

VUR can also be categorized, according to the severity of the condition, into two forms:

Unilateral vesicoureteral reflux

In this form, only one ureter and kidney gets affected.

Bilateral vesicoureteral reflux

In this case, both ureters and kidneys get affected.

Vesicoureteral reflux Grading

There is also an international classification of VUR that has been done on the basis of renal ultrasound examination performed on the affected patients.

Grade 1

It is the mildest form of VUR where only one of the non-dilated ureters is shown to have urinary reflux, preferably due to some bacterial infection.

Grade 2

In this form, reflux of urine occurs into the renal pelvis and calyces under non-dilated conditions.

Grade 3

It is a moderate form of VUR where mild dilation of ureter, renal pelvis, calyces as well as slight blunting of the fornices of the kidney is observed.

Grade 4

In this case, both renal pelvis and calyces are dilated. Moderate tortuosity, where several twists or turns occur in the ureter, is also observed.

Grade 5

This form is marked by a massive dilation of the ureters, renal pelvis and calyces marked by ureteral tortuosity. The distinguishing feature of this high-grade VUR is the damage of papillary impressions. The functional loss is extremely detrimental to the body as it is a region in the kidney where emptying of urine into the minor calyx takes place.

Vesicoureteral reflux Incidence

VUR generally affects 10% of the population. It is prenatally diagnosed in males. However, nearly 85% of cases are reported in females in the later stage of their life.

Vesicoureteral reflux in children

It is more commonly diagnosed in neonates and young children. Approximately 70% of children, who are under the age of 1 year with a urinary tract infection (UTI), are prone to this condition. However, the incidence rate drops down to almost 15% by the age of 12. On the other hand, VUR may affect 17.2-18.5 % of those without UTI.

Vesicoureteral reflux in adults

VUR may affect the adult population as well. It generally occurs in those individuals who had several cases of urinary tract infections in the past.

Vesicoureteral reflux Symptoms

In children, the condition is asymptomatic. In infants with congenital VUR, hydronephrosis is a common characteristic that usually occurs prior to birth. It causes extreme swelling in one of the kidneys due to tremendous pressure. The symptoms are generally visible in the presence of a UTI. Bacterial attack is more likely to occur due to stagnation of urine in the urinary tract. Non-contagious bacteria may often ascend to the upper urinary tract; causing pyelonephritis, which is an inflammatory condition of the kidneys. Although not all patients with VUR experience the same set of symptoms, the disease gives rise to some common problems which include:

  • Fever
  • Fatigue
  • Slow growth
  • Recurrent and painful urination
  • Vomiting
  • Cloudy or blood-laden urine with nauseating odor
  • Diarrhea
  • Lack of appetite
  • High blood pressure
  • GIT infections
  • Kidney malfunction

Vesicoureteral reflux Causes

Most cases of VUR are primary and normally affect young children. Know about the causes of the two main forms of VUR.

Primary Vesicoureteral reflux Causes

In this form, a child is born with an impaired valve present at the junction of the ureter and bladder. Under normal conditions, the valve prevents the backflow of the urine from the bladder to the ureters and kidneys. However, the valve is unable to close properly in this type, thereby causing reflux of urine.

Secondary Vesicoureteral reflux Causes

In this case, a blockage may occur in any region of the urinary tract owing to some form of bladder infection. It ultimately leads to an abnormal swelling of the ureters, causing reversal flow of urine.

Vesicoureteral reflux Diagnosis

Some of the common diagnostic procedures used in the detection of VUR include:

Nuclear cystogram (RNC)

It is a nuclear medicine test where a radiotracer is inserted into the bladder through a catheter. This is followed by an X-ray imaging to evaluate VUR.


This particular test measures the amount of urine in the bladder and kidneys. It is normally conducted before and after urination. An ultrasound device sends high-frequency sound waves to produce images of the urinary bladder and kidneys. Post urination, patients with VUR generally have higher amount of urine left in the ureters and kidneys.

Voiding cystourethrogram (VCUG)

In this diagnostic technique, affected patients are made to lie on an X-ray table. A thin, flexible tube called catheter is inserted into the bladder through the urethra. A radiocontrast agent is used to fill the bladder through the catheter. Patients are made to urinate while the physicians observe the movement of the contrast medium through the bladder. If the contrast agent moves back into the ureters of the bladder VUR can be detected in such individuals, owing to urinary reflux.

Vesicoureteral reflux Treatment

The appropriate treatment options for VUR are based on a few criteria which include factors like:

  • Health status
  • Age
  • Medical history
  • Tolerance towards certain procedures, therapies or medications
  • Severity of the condition

Mild cases of primary VUR do not require any form of treatment and patients generally recover on their own. Early treatment is highly advisable in order to prevent the kidneys from getting permanently damaged. Physicians may either opt for any one of the followings methods:


Antibiotics are usually administered in low dosage to patients with mild secondary VUR to inhibit urinary tract infections. Amoxicillin or Ampicillin is recommendable to infants under two months of age.

Long-term treatment involves antibiotics that are normally administered to infants above two months of age including:

  • Trimethoprim-sulfamethoxazole (co-trimoxazole)
  • Nitrofurantoin (Macrodantin, Furadantin, Macrobid)
  • Nalidixic acid, Bactrim, Cephalosporins
  • Trimethoprim (Primsol)

Endoscopic injection

In this process, an endoscope is used to inject deflux (a gel-like liquid containing complex sugars) in or around the junction of the ureter and kidney. It is generally done to restore the valve function and prevent reflux of the urine into the ureters and kidneys.


The faulty valve at the junction of the ureter and bladder needs to be corrected in the case of primary VUR to prevent retrograde flow of urine.

Cohen cross-trigonal reimplantation is the most frequently performed open surgery for curing this condition. In this process, an incision is made in the bladder and the ureters are relocated into it to prevent urinary reflux.

Laparoscopic reimplantation of the ureters into the bladder is a minimally invasive surgery and is the most preferred one.

Endoscopy is another surgical procedure that is normally performed on infants.

Removal of scarred ureter and kidney may have to be removed in severe cases of VUR.

Vesicoureteral reflux Complications

Due to lack of proper treatment, patients with VUR may suffer from a large number of complications like:

Picture 2 – Vesicoureteral reflux Image

  • Hypertension
  • Renal scarring
  • Acute kidney failure
  • Chronic kidney failure

Fortunately, Vesicoureteral reflux is not a fatal disorder and is curable. Mild degrees of reflux may have a good chance of resolving spontaneously with age and completely disappearing after a certain period of time. However, timely diagnosis is essential before the condition turns serious.

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